Convert object of arrays to array of objects

Question

I have source data in the following format (object of arrays):
{
    value: [
      59, 58, 62, 58, 56, 57, 57, 65, 81, 81
    ],
    dayOfWeek: [
      'Thursday', 'Friday', 'Saturday', 'Thursday', 'Friday', 'Friday',
      'Friday',   'Monday', 'Friday',   'Tuesday'
    ],
    dayOrNight: [
      'N', 'D', 'N', 'D', 'D', 'N', 'N', 'N', 'N', 'N'
    ]
}

And I want the data transformed into the following format (array of objects):
[
    {
        value: 59,
        dayOfWeek: 'Thursday',
        dayOrNight: 'N'
    },
    {
        value: 58,
        dayOfWeek: 'Friday',
        dayOrNight: 'D'
    },
    {
        value: 62,
        dayOfWeek: 'Saturday',
        dayOrNight: 'N'
    },
    ...
]

This is kinda the opposite of this question.
What is the appropriate combination of commands to do this, whether using e.g. lodash or otherwise?

StepUp · Accepted Answer

Combining map method and accessing by key to object, we can achieve desired result:
data.value.map((s, i) => ({value: s, 
   dayOfWeek: data.dayOfWeek[i], dayOrNight: data.dayOrNight[i]}));

An example:


let data = {
    value: [
      59, 58, 62, 58, 56, 57, 57, 65, 81, 81
    ],
    dayOfWeek: [
      'Thursday', 'Friday', 'Saturday', 'Thursday', 'Friday', 'Friday',
      'Friday',   'Monday', 'Friday',   'Tuesday'
    ],
    dayOrNight: [
      'N', 'D', 'N', 'D', 'D', 'N', 'N', 'N', 'N', 'N'
    ]
};

const result = data.value.map((s, i) => ({value: s, 
   dayOfWeek: data.dayOfWeek[i], dayOrNight: data.dayOrNight[i]}));
console.log(result);

UPDATE:
This is slightly modified your approach:


let data = {
    value: [
      59, 58, 62, 58, 56, 57, 57, 65, 81, 81
    ],
    dayOfWeek: [
      'Thursday', 'Friday', 'Saturday', 'Thursday', 'Friday', 'Friday',
      'Friday',   'Monday', 'Friday',   'Tuesday'
    ],
    dayOrNight: [
      'N', 'D', 'N', 'D', 'D', 'N', 'N', 'N', 'N', 'N'
    ]
};

const result = Object.values(data)[0].map((s, i) => {
    let obj = {};
    for (let key in data) {
            obj[key] = data[key][i];
    }
    return obj;
});
console.log(result);

Convert object of arrays to array of objects

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